U.S. Pat. Nos. 6,325,191, 6,615,962, and 7,036,643 are hereby incorporated by reference herein and disclose hydraulic torque converters with one-way clutches.
FIG. 1 shows a prior art hydraulic torque converter 10 including a housing 11 and a pilot 12 coupled with and driven by a prime mover, such as a combustion engine or a crankshaft. Housing 11 has coaxial shells 14 and 16 secured and sealed together, e.g., welded. Attached to housing 11 is a pump 18 coaxial with and sharing the angular motion of housing 11.
Enclosed in housing 11 are a turbine 20 rotatable with respect to housing 11 and a stator 22 installed between pump 18 and turbine 20. Turbine 20 is non-rotatably connected to a turbine hub 24, and turbine hub 24 is non-rotatably connected to element 26, e.g., a transmission input shaft, by splines 28. Stator 22 is mounted on a one-way clutch 30 connected by splines 32 to a hollow, non-rotating stator shaft 34. Axial bearings 36 and 38 are provided at sides of a stator hub 40 and a side plate 42.
One-way clutch 30 includes an outer race 33, blocking elements 35 such as rollers or sprags or individual struts to resist rotation in one direction, and an inner race 31 supporting the blocking elements. Inner race 31 is connected by splines 32 to stator shaft 34. One-way clutch 30 allows stator to only rotate in the same direction that housing 11 rotates around stator shaft 34. Stator shaft 34 may be fixed to a transmission housing.
Torque converter 10 further includes a bypass clutch 44 capable of being engaged to transmit torque directly between housing 11 and turbine hub 24. This is accomplished with a piston 46 which can be moved axially within the housing 11 in order to position a friction surface 48 of piston 46 in contact with a confronting friction surface 50 of housing 11. A torsional vibration damper 52 is installed within the torque path of the bypass clutch 44, between housing 11 and turbine hub 24.